charonn0 / RB-Brotli

A Realbasic and Xojo binding to Brotli

Introduction

Brotli is a generic-purpose lossless compression algorithm with a compression ratio comparable to the best currently available general-purpose compression methods.

RB-Brotli is a Brotli binding for Realbasic and Xojo projects.

Hilights

• Read and write compressed file or memory streams using a simple BinaryStream work-alike.
• A consistent, high-level API over the full range of Brotli's features.
• 64-bit ready
• Interact directly with Brotli using idiomatic RB/Xojo objects, methods, and events; no shell or plugins required.

Getting started

The BrotliStream class is a BinaryStream work-alike, and implements both the Readable and Writeable interfaces. Anything written to a BrotliStream is compressed and emitted to the output stream (another Writeable); reading from a BrotliStream decompresses data from the input stream (another Readable).

Instances of BrotliStream can be created from MemoryBlocks, FolderItems, and objects that implement the Readable and/or Writeable interfaces. For example, creating an in-memory compression stream from a zero-length MemoryBlock and writing a string to it:

  Dim output As New MemoryBlock(0)
  Dim z As New BrotliStream(output) ' zero-length creates a compressor
  z.Write("Hello, world!")
  z.Close

The string will be processed through the compressor and written to the output MemoryBlock. To create a decompressor pass a MemoryBlock whose size is > 0 (continuing from above):

  z = New BrotliStream(output) ' output contains the compressed string
  Dim decompressed As String
  Do Until z.EOF
    decompressed = decompressed + z.Read(1024) ' read the decompressed string
  Loop
  MsgBox(decompressed)

How to incorporate Brotli into your Realbasic/Xojo project

Import the Brotli module

1. Download the RB-Brotli project either in ZIP archive format or by cloning the repository with your Git client.
2. Open the RB-Brotli project in REALstudio or Xojo. Open your project in a separate window.
3. Copy the Brotli module into your project and save.

Ensure the Brotli shared libraries are installed

Brotli is not installed by default on most systems, and will need to be installed separately (or shipped with your app). Pre-built binaries for Windows can be downloaded from the libcurl project. You will need libbrotlicommon.dll, libbrotlidec.dll, and libbrotlienc.dll.

RB-Brotli will raise a PlatformNotSupportedException when used if all required DLLs/SOs/DyLibs are not available at runtime.